When it comes to paddy crops, false smut is a serious issue that farmers need to recognize. In this blog, we will talk about what false smut is, how it affects crops,favourable factors,its symptoms of damage and effective strategies for controlling and preventing its spread.
What is False Smut of Paddy?
In paddy crops, False smut, caused by the fungus Ustilaginoidea virens, primarily affects the individual rice grains within the panicle. However, it doesn't directly impact other plant parts. The percentage of infected panicles and the extent of infection within each panicle significantly impact yield loss. More severe infections with a high number of affected panicles and heavily impacted grains within each panicle can lead to much higher losses.
Overview of False Smut of Paddy Crop
Type of Infestation |
Disease |
Common Name |
False Smut |
Causal Organism |
Ustilaginoidea virens |
Affected parts of the plant |
Rice Grain |
What are the favorable factors for False Smut in Paddy crops?
- Warm and humid weather: Temperatures between 25-30°C and high humidity (>80%) promote fungal growth.
- Presence of infected plant debris: Spores can survive on leftover stubble and straw from previous harvests.
- High nitrogen content in soil: Excessive nitrogen application can increase susceptibility.
Symptoms of False Smut in Paddy Crop
- Individual rice grains transformed into masses of yellow or greenish-black spore balls. These balls are initially orange, gradually turning yellowish-green or greenish-black as they mature.
- Size varies, typically reaching up to 1 cm in diameter.
- Only a few grains per panicle are usually infected, but neighboring grains often remain unfilled.
- Reduction in grain weight due to chalkiness caused by the fungus.
- Decreased seed germination if infected grains are used for sowing.
Measures to control False smut in paddy:
Cultural method of control:
- Among the cultural control, the destruction of straw and stubble from infected plants is recommended to reduce the disease
- At the time of harvesting, diseased plants should be removed and destroyed so that sclerotia do not fall into the field. This will reduce the primary inoculum for the next crop.
- Avoid field activities when the plants are wet
Chemical Control of False Smut in Paddy Crop:
- In areas where the disease may cause yield loss, applying captan, captafol, dentin hydroxide, and mancozeb can inhibit conidial germination.
- At tillering and flowering stages, spraying of carbendazim fungicide and copper base fungicide can effectively control the disease.
Products |
Technical Names |
Dosages |
Azoxystrobin 11.00 % Tebuconazole 18.30 % SC |
300ml/Acre |
|
Azoxystrobin 18.2 % + difenoconazole 11.4 % SC |
150-200ml/Acre |
|
Propiconazole 25 % EC |
200-300ml/acre |
|
Carbendazim 12 % + Mancozeb 63 % WP |
300-400gm/acre |
FAQs related to False Smut in Paddy Crop
Q. What is the False Smut of Paddy crop?
A. False smut is a fungal disease caused by the fungus Ustilaginoidea virens
Q. Which is the best fungicide for False Smut of Paddy?
A. Fungicides like Azoxystrobin 11.0%, Propiconazole, carbendazim, and Mancozeb are the best fungicides for the management of False smut of Paddy
Q. what are the symptoms of False smut in paddy crops?
A. Individual rice grain transforms into a mass of yellow fruiting bodies,Growth of velvety spores that enclose floral parts and Infected grain has greenish smut balls with a velvety appearance.